INSECTS INJURIOUS TO SMALL GRAINS 121 



Unfortunately this practice is often impossible, owing to the prac- 

 tice of seeding wheat land to grass and clover. 



As early volunteer plants always become badly infested and the 

 pupae wintering on them give rise to a spring brood which attacks 

 the main crop, all volunteer plants should be destroyed by plowing 

 or disking before the larvae have matured. This principle has some- 

 times been utilized in the form of a trap crop, strips of wheat being 

 sown early so as to attract the flies and then being plowed under 

 after the bulk of the eggs had been laid upon them, thus protecting 

 the main crop, planted later. 



The enrichment of the soil, the preparation of a good seed bed, 

 and the use of good seed, so as to secure a vigorous growing crop, 

 are all of the greatest importance in overcoming injury by the 

 Hessian fly. After the crop is once attacked, no truly remedial 

 measures are known except to apply liberally some quick-acting 

 fertilizer which will cause the plants to tiller freely and give them 

 sufficient vigor to withstand the winter and thus increase the 

 healthy stems the next spring. 



Of late years the practice in some of the principal wheat growing 

 states, notably in Kansas, has been to plow the wheat stubble 

 under deeply, destroy all volunteer plants and to roll or pack 

 in some manner the soil in the plowed fields so that the adult 

 flies will be unable to make their escape from the buried pupie. 

 This is recommended as the best means of control but may well 

 be practiced along with sowing after the "fly-free" date as deter- 

 mined for the region in question. 



Some work with immune or partially immune varieties is in 

 progress but no results of a definite nature have been announced. 



Keeping the soil in first class condition and practicing rotation 

 and other matters of the best farming practice will help to keep the 

 damage from the fly from being so serious during any season as 

 it might otherwise have been. 



The Wheat Joint-worm * 



For the last sixty years the joint- worm has been known as 

 a serious pest of wheat throughout the wheat-growing region 

 east of the Mississippi River, the damage varying from a 



* Harmolita triiici Fitch. Family Chalcididce. 



See W. J. Phillips, U. S. Dept. Agr. Bulletin 808, and Farmers' Bul- 

 letin 1006^ 



